Apparati for use in packaging plastic bottles in plastic bags are known. For example, a manual-operated bagger comprises a loading platform, a plurality of vertical walls framing the platform and a roller rotatably mounting a roll of plastic bags. In operation, rows of bottles are positioned on the platform within the confines of the vertical walls and thereafter cardboard is placed on the tops of the bottles. A second layer of bottles is then positioned on top of the cardboard and a second cardboard is set on the tops of the second layer of bottles. This process of stacking layers of bottles separated by layers of cardboard continues until the platform is filled. Thereafter, the roller is rotated and a plastic bag is drawn off the roll and over the vertical walls and the platform. The platform is then rotated and the bag packaging the bottles is removed out of engagement from the walls and the platform. Once so removed, the open end of the bag is sealed by a suitable mechanical means.
The principal drawback of the manual bagger is its inefficiency. Since the bagger is manually operated, the speed at which bottles can be bagged is limited to the speed at which the operating can operate the bagger. In addition, the bottles bagged by the bagger are subjected to unsanitary conditions. The cardboard used in the bagging process is associated with dirt and dust which inevitably contaminates the interior of the bottles. This presents a sanitation problem for those in the dairy industry wherein bottles packaged by the bagger are shipped to dairies for filling with milk. If the bottles are contaminated, the dairies are required to clean the bottles prior to the filling process. This cleaning process is relatively expensive. Further, the cardboard is an expense which could be avoided.
Another bottle bagger currently available is manufactured by Dyco, Inc., of Berwick, Penna. This bagger comprises first and second platforms set in offset juxtaposition with respect to one another. The first platform has a first end and a second end and a first pusher is movable between the first and second ends. The second platform has first and second sides and a second pusher is movable between the second end of the first platform and the first side of the second platform. A third pusher is movable between the first and second sides of the second platform. The bagger also includes bag holder and sealing assemblies positioned midway between the first and second sides of the second platform. The bag holder assembly holds a bag such that the opened end of the same faces the first side of the second platform. In operation, bottles are first fed seriatim by a conveyor onto the first end of the first platform until a row of bottles is allowed to accumulate thereon. The row is then moved onto the second end of the first platform by the first pusher. After a predetermined number of rows of bottles have so accumulated on the second end of the first platform, the second pusher moves the rows of bottles laterally from the second end of the first platform to the first side of the second platform. The third pusher then forces the bottles into the bag. Sealing jaws of the sealing assembly subsequently close the open end of the bag and a pair of heated wires on the jaws seal the bag and sever excess plastic of the bag at the seal. The sealed bag packaging the bottles is thereafter moved off the second side of the second platform for storage or shipping.
The main drawback of the Dyco bagger is its inefficiency. As stated above, each row of bottles fed onto the first end of the first platform is individually pushed by the first pusher the full distance between the first and second ends of the first platform. This process of accumulating a plurality of rows of bottles on the second end of the first platform is time consuming.
To improve the speed at which a bagger can accumulate a plurality of rows of bottles so that they can thereafter be pushed into a bag for packaging, it has been found desirable to push each row of bottles fed onto a first end of a platform a relatively short distance sufficient to allow another row of bottles to be loaded onto the first end of the platform. These short movements of a pusher on the first end of the platform would continue until a predetermined number of rows of bottles accumulate on the first end whereupon the pusher then forces the accumulated rows the full distance to a second end of the first platform for loading into the bag. It has been found that this latter process is twice as fast as the former process of pushing each row of bottles individually from one end of a platform to another end of the same. A packaging machine of this type, i.e., wherein individual rows of articles are successively pushed downstream on a platform a relatively short distance by a pusher and thereafter pushed into a bag, is disclosed in Bowes U.S. Pat. No. 2,613,021, issued Oct. 7, 1952. Applicants' assignee's copending U.S. patent application Ser. No. 880,127 for an Automatic Bottle Bagger discloses a similar apparatus.
To further improve the speed at which a packaging apparatus can bag articles, it has been found desirable to provide a bagger wherein rows of bottles are accumulated on a pair of side platforms in the desired manner described above and thereafter alternately moved onto a central platform and pushed into plastic bags. This bagger also permits the alternate bagging of bottles of different type from the two side platforms.